import axios from 'axios'
import { config } from '@things-factory/env'

/**
 * Label Studio SSO Service
 *
 * Handles JWT token acquisition from Label Studio for SSO authentication.
 * The client application requests JWT tokens from Label Studio's token API,
 * then uses cookie-based authentication to automatically log users in.
 */
export class LabelStudioSSOService {
  /**
   * Get Label Studio SSO configuration
   */
  private static getConfig() {
    const labelStudioConfig = config.get('labelStudio', {
      serverUrl: 'http://localhost:8080',
      apiToken: ''
    })

    return {
      serverUrl: labelStudioConfig.serverUrl,
      apiToken: labelStudioConfig.apiToken
    }
  }

  /**
   * Request JWT token from Label Studio for SSO authentication
   *
   * @param email User email address
   * @returns JWT token and expiry time, or null if failed
   *
   * @example
   * ```typescript
   * const tokenData = await LabelStudioSSOService.getSSOToken('user@example.com')
   * if (tokenData) {
   *   console.log('Token:', tokenData.token)
   *   console.log('Expires in:', tokenData.expires_in, 'seconds')
   * }
   * ```
   */
  static async getSSOToken(email: string): Promise<{ token: string; expires_in: number } | null> {
    const { serverUrl, apiToken } = this.getConfig()

    if (!apiToken) {
      console.error('[LSS SSO] Label Studio API token not configured')
      return null
    }

    if (!email) {
      console.error('[LSS SSO] Email is required')
      return null
    }

    try {
      console.log(`[LSS SSO] Requesting JWT token for: ${email}`)

      const response = await axios.post(
        `${serverUrl}/api/sso/token`,
        { email },
        {
          headers: {
            'Authorization': `Token ${apiToken}`,
            'Content-Type': 'application/json'
          },
          timeout: 5000
        }
      )

      const { token, expires_in } = response.data

      console.log(`[LSS SSO] JWT token acquired for ${email} (expires in ${expires_in}s)`)

      return { token, expires_in }
    } catch (error: any) {
      if (error.response) {
        console.error(`[LSS SSO] Label Studio API error: ${error.response.status}`, error.response.data)
      } else if (error.request) {
        console.error('[LSS SSO] No response from Label Studio:', error.message)
      } else {
        console.error('[LSS SSO] Request error:', error.message)
      }

      return null
    }
  }

  /**
   * Verify SSO configuration is properly set up
   *
   * @returns True if configuration is valid
   */
  static verifyConfig(): boolean {
    const { serverUrl, apiToken } = this.getConfig()

    if (!serverUrl) {
      console.error('[LSS SSO] Label Studio server URL not configured')
      return false
    }

    if (!apiToken) {
      console.error('[LSS SSO] Label Studio API token not configured')
      return false
    }

    return true
  }
}